The present invention relates generally to lighting systems which are primarily intended for use in connection with motor vehicles, and more particularly, to a lighting assembly which can be variably directed in accordance with a user's needs.
Conventional motor vehicles traditionally incorporate one or more headlights to enable use of the vehicle during night hours. Many times, auxiliary lighting systems in addition to those already incorporated in the vehicle are used to accommodate special driving conditions such as fog, mist, poorly lit roads, etc. Often, these auxiliary systems are placed on peripheral structures associated with the vehicle such as bumpers, fenders and roll-bars.
Generally, both types of lighting systems are fixedly attached to the associated vehicle. As a result, the beam of light developed by such systems is only projected from the vehicle in a single direction. Of course, this is generally acceptable for conventional lighting applications. However, a need has long been recognized for a lighting system which is capable of projecting a directionally variable beam of light to accommodate special needs.
For example, in some applications it has become desirable to develop a lighting system which is capable of varying the elevation of the beam of light projected, primarily to correct for changes in vehicle attitude which may result from unusual vehicle loading. U.S. Pat. Nos. 4,276,581; 4,195,327; and 4,066,886 each illustrate examples of systems capable of providing such a function. In each case, when unusually heavy loads are placed in the trunk (or tailgate) of the vehicle, headlight elevation is varied in accordance with resulting changes in vehicle attitude, in turn correcting projection of the beam of light from the vehicle to accommodate the unusual loading.
In other applications is has become desirable to develop a lighting system which is capable of steering the projected beam of light together with the vehicle, primarily to light a road as the vehicle traverses a corner. U.S. Pat. Nos. 3,116,026 and 1,974,371 each illustrate examples of systems capable of providing such a function. In each case, a mechanism ssociated with the steering system of the vehicle causes simultaneous rotation of a headlight assembly, in turn causing the beam of light projected to follow the curvature of the road being traversed.
One other application which has received attention is the development of a lighting system which is capable of directional variation, both horizontally and vertically, preferably in accordance with the needs of the vehicle's operator. U.S. Pat. No. 2,639,367 illustrates an example of one such system, which utilizes a system of mechanical linkages and gearing arrangements to provide the desired result. However, the system illustrated is relatively complicated in that it comprises a significant number of interrelated moving mechanical parts, compromising its cost, utility and precision, and accordingly, its public acceptance.
It therefore remains desirable to develop a lighting system which is capable of directing a beam of light both horizontally and vertically, in accordance an operator's needs, and which is flexible in operation and simple in construction.